1. Field of the Invention
The present invention relates to a projector, and in particular to a projector capable of detecting the remaining lifetime of its light source lamp, as well as the detecting method thereof.
2. Description of the Related Art
Conventionally, projectors optically process a light beam emitted from a light source to form an optical image, while enlarging and projecting the optical image through a projection lens. Such projectors are widely used for multimedia presentations. Typically, light source lamps, such as metal halide lamps, xenon lamps and the like, are used in projectors as the light sources.
While such a light source lamp can emit relatively stable light for several hours after it is put into use, lamp use beyond that limit may exceed the usable life of the lamp, wherein luminance is considerably reduced. The lamp may burn out and potential danger may be produced due to gradually increasing lamp voltage caused by exceeding the effective lifetime of the lamp.
For this reason, conventional projectors accumulate the time used of the lamp therein by a timer, and advise replacement with a new lamp when the accumulated lifetime of the lamp exceeds a predetermined time. However, different tolerances still exist between lamps, even within the same type. Namely, in the same type of lamps, some lamps burn out while others may be used for a short time even when exceeding the predetermined usable time. As well, the usable time of lamps operated at high brightness is less than of those operated at low brightness, thus, waste occurs if the lamp is replaced with a new one in accordance with only the estimated lifetime of the lamp.